Syphilis, Chlamydia Rates Go Up in U.S.

Nov. 8, 2005 -- Reported cases of syphilis rose an alarming 8% between 2003 and 2004, worrying national health officials that sexually risky behavior is again on the rise in the U.S.

The increase extended a steady rise in sexually transmitted syphilis infection since 2000, when rates reached a 50-year low. Two-thirds of the new infections are now in men who have sex with men, what public health officials refer to as "MSMs," and are focused primarily among blacks in U.S. cities.

Nearly 8,000 syphilis cases were reported to federal officials in 2003. Though overall infection numbers remain relatively low, infection rates among those men were up more than 80% between 2000 and 2004.

Officials also reported a 6% rise in cases of chlamydia in 2003. CDC recorded more than 900,000 cases, though officials estimated that as many as 2.8 million new infections occur each year.

"Reported chlamydia cases are just the tip of the iceberg," says Ronald O. Valdiserri, MD, acting director of HIV, STD, and TB prevention programs at the CDC.

Valdiserri says improved testing and diagnosis were the primary drivers behind the increase in reported chlamydia cases and that researchers have little evidence of overall increases in the disease's spread.

Still, chlamydia exacts a heavy toll on teenaged girls between 15 and 19 years old and women between 20 and 24 years old, who are the most likely groups to contract the bacteria through unprotected sex. Chlamydia usually causes no symptoms in women but can lead to pelvic inflammatory disease and complications of ectopic pregnancy and infertility if left untreated.

The CDC has recommended annual chlamydia testing for all sexually active women younger than 26 years of age, but few young women receive the tests, according to Douglas.

"Most cases of the disease remain undiagnosed and untreated," he says.

Higher Rates Among Minority Groups

Officials pointed to increasing racial disparities in syphilis, chlamydia, and gonorrhea rates. All of the diseases are now substantially more likely to infect blacks and other minority groups than they are whites, according to CDC figures. Black women were nearly eight times more likely than white women to contract chlamydia in 2003, Tuesday's CDC report noted.